Process for manufacturing a touch fastener part

摘要

A thermoplastic film strip(2) is fed onto a metal forming roll(3) whose surface is covered by a rubber layer(7) in which laser-cut blind holes(4) are formed. The film strip is pressed into the holes by a heated compression and smoothing roll(6) to produce pins(15) in the strip. A thermoplastic film strip(2) is fed onto a metal forming roll(3) whose surface is covered by a rubber layer(7) in which laser-cut blind holes(4) are formed. The film strip is pressed into the holes by a heated compression and smoothing roll(6) to produce pins(15) in the strip. The strip is drawn off between a heated take-off roll and a heated PTFE(polytetrafluoroethylene) coated pressure roll where at low strip speeds gripping heads are formed by compression of the pins. At higher strip speeds the heads are produced by a plasma head and arc. Preferred Features: The rubber layer on the heated forming roll has a PTFE coating 3-5microns thick. The pressure roll runs at not less than230[deg]C. Roughening of the metal base of the heated forming roll enhances the bond with the rubber layer.